Senior AI Engineer - Build AI-Powered User Experiences

PortX, Inc.; Seattle (WA); Hybrid; USD 160,000 - 190,000; Full time

Benefits offered by this job

Equity package

Insurance (medical, dental, vision)

Unlimited PTO

401(k)

Job summary

PortX, Inc. is seeking a Senior AI Engineer to design, integrate, and optimize AI-driven features across web and mobile apps.

You will work with large language models, agents, and third-party APIs to craft intelligent user experiences, while focusing on production-ready workflows and scalable architectures. The role emphasizes practical AI integration, not model training, and offers a competitive salary with equity, comprehensive insurance, unlimited PTO, and a 401(k).

Qualifications

• 5+ years of software engineering experience, backend or full-stack focus.
• Strong Python programming skills and production services experience.
• Experience with AI agents and agent frameworks (LangChain, Semantic Kernel, or similar).
• API and front-end development with modern frameworks like JavaScript/TypeScript and React.
• Familiarity with foundation model APIs (OpenAI, Anthropic, Cohere, Google).
• Experience with prompt engineering, tool orchestration, and LLM-based interactions.
• Understanding of REST APIs, embeddings, vector stores, and evaluation workflows for AI performance.

Responsibilities

• Design and build AI-powered product features using OpenAI, Claude, Vertex AI, and custom APIs.
• Prototype intelligent user experiences including chat interfaces and workflow automation.
• Integrate third-party AI models into web and mobile apps with a focus on security and scalability.
• Collaborate with product and design teams to translate AI capabilities into intuitive user experiences.
• Fine-tune prompts, orchestration logic, and fallback behaviors for reliable outputs.
• Work with data and backend teams to stream relevant data into AI features.
• Monitor and improve real-world AI performance with human-in-the-loop and analytics.

Skills

Python

AI agents

API design

Front-end interfaces

LLM interactions

Tools

OpenAI

Claude

Vertex AI

custom APIs

Job description

PortX, Inc. is seeking a Senior AI Engineer to design, integrate, and optimize AI-driven features across web and mobile apps.

You will work with large language models, agents, and third-party APIs to craft intelligent user experiences, while focusing on production-ready workflows and scalable architectures. The role emphasizes practical AI integration, not model training, and offers a competitive salary with equity, comprehensive insurance, unlimited PTO, and a 401(k).